甲基丙烯酸改性甲基丙烯酸β羟乙酯水凝胶义眼台的实验研究

目的研究兔眶内植入甲基丙烯酸(MMA)改性甲基丙烯酸β羟乙酯(PHEMA)水凝胶义眼台的生物相容性和纤维血管化情况,为其临床应用奠定实验基础。方法将直径为14 mm的MMA改性PHEMA水凝胶义眼台分别手术植入32只兔眼眶内,分别于术后2、4、8、12及24周做单光子发射型计算机体层摄影术(SPECT)检查,并在不同时间点(2、4、8、12及24周)取出植入物进行光镜、免疫组化(Actin、Vimentin、CD34)及电镜观察。结果 SPECT检查改性PHEMA植入物在在体情况下随时间延长,同位素示踪剂在局部逐渐浓集。光镜、免疫组化、电镜检查结果显示2周时纤维血管组织从植入物外周长入,4～8周孔隙内胶原纤维逐渐致密,至12周全部纤维血管化。32例中仅1例术后出现结膜裂开、义眼台暴露,经二次手术修补愈后好。结论经改性的PHEMA水凝胶义眼台组织相容性好、血管化快,手术操作简单,并发症少,是一种安全、实用的新型眶内植入材料。     

102例国产羟基磷灰石眼窝填充术的疗效评价与SPECT观察

本文对８８例患者采用国产羟基磷灰石（ＨＡ）填充球，施行眼球摘除，自体巩膜壳包裹球体的眶内Ⅰ期植入；和１４例无眼球患者行Ⅱ期眶内填充术。追踪观察６—３６个月，疗效满意，未发现球体脱出、移位，植入球体性能稳定可靠，眼睑饱满，义眼活动良好。随机１１例术后１个月以上病例进行单光子发射计算机断层摄影（ＳＰＥＣＴ），从眼眶断层检查中发现８个月以上者，ＨＡ球体放射性分布明显增强，感兴趣区放射性计数比值高于健眼１８—４４％。以放射性分布图象作为眼窝纤维血管长入ＨＡ球体内的依据，说明术后８个月以上者球体可完全血管化。     

多孔羟基磷灰石眶内植入物血管化的影响因素

珊瑚多孔羟基磷灰石(CHA)眶内植入物完全血管化不仅可以保证活动义眼安装成功率,而且可减少植入术后的结膜裂开、植入物暴露、移位、感染等并发症的发生,它是羟基磷灰石眶内植入术成功与否的关键之一.本文就CHA材料因素、手术方式、包裹CHA的材料、促生长因子、高压氧、激光等方面对羟基磷灰石眶内植入物完全血管化的影响因素做一综述.     

羟基磷灰石眶内植入物并发症的预防与处理

目的 探讨羟基磷灰石（ｈｙｄｒｏｘｙａｐａｔｉｔｅ,ＨＡ）眶内植入物并发症发生原因及其处理。方法 对４０例ＨＡ眶内植入物并发症患者采取眼球筋膜囊扩张缝合术、ＨＡ人工骨眶内充填术等方法进行处理,并随访观察。结果 共有植入物暴露、残留上眶区凹陷及移位等６种并发症,结过处理均获得较好效果。结论 ＨＡ眶内植入物并发症的类型及其原因是多方面的,通过相应处理,可以控制。     

肌腱在鸡眼窝成形术中的应用

目的 以鸡为模型，研究同种异体肌腱植入眶腔后的组织相容性及纤维血管化的情况。方法 在18只鸡眼眶内植入经超代温冷冻技术灭活抗原后的同种异体肌腱，于术后定期取出植入物做病理组织学检查。结果 18例中无植入物暴露及明显排斥反应，术后3周肌腱组织有肉芽组织增生，钙化。8周时有纤维结缔组织增生，有毛细血管生长。24周时有较多毛细血管，纤维组织增生明显。结论 经灭活抗原处理的同种异体肌腱具有良好的组织相容性。     

珊瑚羟基磷灰石Ⅱ期眶内植入

目的：观察眼球摘除后羟基磷灰石眼座二期眶内植入的修复疗效。方法：用珊瑚多孔羟基磷灰石作为二期眶内植入物共253例。结果：随访6个月-15个月均获得良好的效果。并发症少,未发现眶内感染,植入物排出移位现象,结论：珊瑚羟基磷灰石并发症少,是目前眼球摘除后的良好眶内充填材料。     

羟基磷灰石眶内植入物血管内皮细胞生长因子的表达

目的:探讨血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)与羟基磷灰石(hydroxyapatite,HA)眶内植入物纤维血管化形成的相关性,以及地塞米松抑制羟基磷灰石植入物纤维血管化的机制。方法:家兔20只随机分为实验组与对照组,每组10只;各组均采用HA植入物植入兔眼眶。术后滴妥布霉素滴眼液4次/d,实验组术后48h起隔日球周注射地塞米松0·5mg和实验结束,并观察两组的结膜生长情况;实验组与对照组分别于术后3,7,14,21,28d摘取2只HA植入物行免疫组织化学检测VEGF阳性表达情况。结果:羟基磷灰石植入物纤维血管化与VEGF的表达存在显著的相关性。术后14d,实验组HA炎性细胞浸润明显减少,实验组VEGF表达明显低于对照组。结论:羟基磷灰石植入物纤维血管化与炎症反应密切相关,VEGF可能参与了纤维血管化形成过程,地塞米松可能通过抑制植入物的炎症反应及VEGF的表达。     

核素闪烁扫描对羟基磷灰石植入物血管化的评估

了解羟基磷灰石眶内植入物血管化过程。方法应用核素闪烁扫描对１７只兔眼实验性眶内羟基磷灰石植入术后和２２例羟基磷灰石植入眼窝成形术患者植入物内血 入状况进行检查。所得感兴趣区放射性平均计数比值。应用负指数饱和增长模型公式统计。     

脱细胞真皮包裹PHEMA水凝胶义眼台的实验研究

目的:研究脱细胞真皮包裹的水凝胶义眼台复合物的制备方法,评价其生物学性能。方法:材料制备:用MMA和HEMA的聚合物单体加入NaCl成孔剂制备多孔水凝胶义眼台,750mL/L乙醇浸泡制备同种异体巩膜包裹物。动物实验:新西兰白兔32只,右眼球摘除术后,16只植入脱细胞真皮包裹的直径为12mm的水凝胶义眼台作为实验组,16只植入保存异体巩膜包裹的直径为12mm的水凝胶义眼台作为对照组,术后在不同时间点(2,4,8,12wk)取材作病理检查,比较不同包裹材料对义眼台血管化程度和义眼台植入并发症发生率影响的差别。结果:MMA和HEMA的聚合物单体体积膨胀率为1.2,孔隙率为72%,孔径大小为450～520μm,且多为通孔。不同材料包裹PHEMA多孔水凝胶义眼台植入兔眶腔术后,所有32眼无肉芽肿发生及义眼台排出。光镜结果显示纤维血管组织2wk时从植入物外周长入,4～8wk时孔隙内胶原纤维逐渐致密,12wk时完成纤维血管化,扫描电镜显示植入物孔隙内逐渐被纤维血管组织填充,2wk时纤维血管组织附壁生长,12wk时孔隙内被纤维血管组织充满且孔间相连。对各组植入物纤维血管化程度进行测量,结果进行多因素方差分析,实验组较对照组血管化速度快(P=0.01)。结论:PHEMA水凝胶义眼台和脱细胞真皮生物相容性好,是一种安全可靠的眶内植入物,符合临床应用的要求,具有潜在的实际应用价值。     

牛骨异种移植物作为义眼座兔眼眶内植入术

目的:评价以牛骨作为义眼座在兔眼眶内植入的生物相容性。方法:在兔眼中用牛骨作为植入物,观察其生物相容性及其能否取代昂贵的人造植入物。把12只眼球内容摘除术后的新西兰白兔按眶内有没有植入牛骨分为两组:Y组(6只)为眼球摘除术后眶内没有植入牛骨,X组(6只)为眼球摘除术后植入牛骨。对12只新西兰白兔右眼行眼球内容物摘除,其中6例作为实验组行牛骨植入,6例作为对照组不植入。术后1,7,14,28,42d连续观察术眼的感染情况,植入物的移位情况,伤口愈合情况,眼球运动是否受限。术后42d,摘除实验组眼球,行组织病理检查,检测其炎性反应类型以及纤维血管增生情况。结果:连续临床观察显示:试验组和对照组在术后1d都有轻微的炎症反应,抗生素控制有效。试验组有1例在术后1d发生感染。但没有植入物的移位和脱出,没有伤口的裂开和眼球运动受限,也没有严重的感染和畸形出现。组织病理检查显示牛骨纤维生长良好,有轻微的排斥反应。结论:实验表明在兔眼中,牛骨作为义眼座植入有良好的生物相容性,而且其成本较低,易被接受。     

羟基磷灰石义眼台纤维血管化的MRI实验研究

目的用磁共振成像（MRI）研究兔眼眶内植入羟基磷灰石（HA）义眼台血管化过程，探讨义眼台血管化MRI的表现和特点。方法12只新西兰白兔眼眶内植入直径12mm天然HA义眼台，于术后第1、2、3、4、5、6周对所有手术兔行双眼磁共振（MR）平扫及Gd—DTPA增强扫描，计算义眼台强化区体积与义眼台体积比值（VE／VHA），对结果用方差分析（q检验）。并于第2、4周随机抽取2只，第6周对剩余动物义眼台行组织病理学检查。结果术后第1、2、3、4周VE／VHA值逐渐增加，均数间比较差异有统计学意义（F=240．654，P=0．000），第4周与第5、6周比较差异无统计学意义（F=0．686，P=0．520）。术后第2周病理显示义眼台周边有纤维血管生长，第4、6周整个义眼台完全血管化。结论MRI可直观、准确地评价义眼台血管化的程度和范围。     

Glass-ionomer cement: evaluation as an orbital implant

· Background: To assess the potential of a porous glass-ionomer cement (GIC) as an alternative material for spherical orbital implants, the handling, side effects and rates of fibrovascular ingrowth of this material were compared with those of a synthetic hydroxyapatite (HA) implant. · Method: Twenty-one GIC and 8 HA uncovered 14-mm spheres were implanted into the orbits of New Zealand albino rabbits. Postoperative reactions, animal’s behaviour, weight increase and socket conditions were monitored. Light and electron microscopy of the exenterated orbits were performed 2, 3 and 6 months after primary insertion. · Results: Implanting of GIC was easier than HA. Postoperatively all animals did well. Three HA and 1 GIC implant caused conjunctival dehiscences, but no implant extrusion was observed. Histologically, both materials caused mild inflammation in the surrounding connective tissue capsule, decreasing with time. GIC implants proved to be not truly porous, with only peripheral pores partly occupied by relatively acellular collagenous connective tissue. Free glass particles were observed in both the connective tissue and giant cells, occupying the partly filled pore spaces. HA implants showed extensive ingrowth of vital host tissue from the beginning. · Conclusions: Considering the clinical findings and the mild inflammation in the connective tissue capsule surrounding both materials, they would appear to be equally well tolerated at the implant site. The significantly different microstructure and the histological results make GIC, despite better handling, less suitable as an orbital implant. Received: 31 October 1997 Revised version received: 20 April 1998 Accepted: 12 May 1998     

The influence of hyperbaric oxygen therapy and irradiation on hydroxyapatite ocular implant exposure and fibrovascular ingrowth in New Zealand white rabbits

PURPOSE: Lack of adequate fibrovascular ingrowth has been implicated as a cause of exposure of hydroxyapatite (HA) implants in anophthalmic sockets. We investigated the vasculopathic effects of external beam irradiation, and the fibrovascular-enhancement effects of hyperbaric oxygen (HBO), on HA implant exposure and fibrovascular ingrowth in a rabbit model. METHODS: Eighteen rabbits underwent enucleation with implantation of a 12-mm HA sphere. Six rabbits received 20 Gy of external beam orbital irradiation prior to enucleation. Three irradiated and 6 nonirradiated rabbits received postoperative HBO. Three weeks postoperatively, all rabbits were evaluated clinically for evidence of implant exposure. Implants were then removed, and histopathologic analysis of fibrovascular ingrowth was performed. RESULTS: The amount of vascularization as measured by the depth of ingrowth was greater for nonirradiated (89% ingrowth) than for irradiated (71% ingrowth) animals. HA implant exposure occurred in 1 of 12 (8%) of the nonirradiated, and 4 of 6 (67%) of the irradiated rabbit orbits. HBO did not protect irradiated rabbits from exposure, but did enhance fibrovascular ingrowth in nonirradiated rabbits (100% ingrowth vs. 77% ingrowth). CONCLUSION: Impaired orbital vascularization from prior irradiation appears to retard fibrovascular ingrowth into HA implants, and is associated with an increased incidence of exposure. While HBO did not diminish the likelihood of exposure in irradiated sockets, HA fibrovascular ingrowth in normal orbits appeared to increase with HBO. This may have beneficial clinical application in cases of exposure in nonirradiated orbits.     

Fibrovascular ingrowth in porous ocular implants: the effect of material composition, porosity, growth factors, and coatings.

PURPOSE: Fibrovascular ingrowth into various porous ocular implants as a function of implant material composition, porosity, growth factors, and coatings was investigated in a pilot study in an animal model. METHODS: Eighty-one New Zealand white rabbits underwent unilateral enucleation and implantation with ocular implants composed of the following materials: coralline hydroxyapatite (HA) with 200-microm pores (HA200) or 500-microm pores (HA500), synthetic HA (synHA), and high-density porous polyethylene (PP). The HA200, HA500, and PP implants were implanted untreated or after treatment with recombinant human basic fibroblast growth factor (Rh-bFGF). Nine HA500 implants were implanted after coating with calcium sulfate (plaster of Paris) to provide a smooth outer surface. Implants were harvested at 1-, 2-, 4-, or 8-week intervals and were examined histologically. RESULTS: A significant difference was found between untreated HA500 and PP, with PP showing better ingrowth. There was no significant difference between untreated HA and PP, nor between untreated HA500 and synHA. Significant increases in ingrowth were found in HA200 compared with HA500, and in Rh-bFGF-treated implants compared with untreated controls. The calcium sulfate-coated implants showed less vascularization compared with the uncoated implants, although the difference was not significant. CONCLUSIONS: Fibrovascular ingrowth occurred earlier in HA200 implants than in HA500 implants, and was enhanced when implants were treated with Rh-bFGF.     

碱性成纤维细胞生长因子应用于羟基磷灰石眶内植入物的研究

目的 观察不同浓度的碱性成纤维细胞生长因子（basic fibroblast growth factor,bFGF)对羟基磷灰石（hydroxyapatite,HA）植入物纤维血管化的作用。方法 将36只新西兰白兔随机分为A、B、C、D4组,每组9只,各组均采用HA植入物植入兔眼眶。A组为对照组,B、C、D组在HA球植入术前将植入物分别浸泡于浓度为0.5、1.5及5.0g/L国产重组bFGF溶液中,术后B、D、D组术眼分别滴用上述不同浓度bFGF的眼液。各组分别于术后14、28及42d摘取HA植入物行组织学检查,并比较各组不同时间的植入物纤维血管化的情况。结果 术后14d,纤维血管从HA植入物外周长植入物内距离,C、D与A、B组比较,差异有显著性（χ^2=9.0,P=0.029）。结论 1.5及5.0g/L浓度的bFGF液对HA植术物术后早期的纤维血管化具有促进作用。     

碱性成纤维细胞生长因子应用于羟基磷灰石眶内植人物的研究

目的观察不同浓度的碱性成纤维细胞生长因子(basic fibroblast growth f     

Coralline hydroxyapatite orbital implant (bio-eye): experience with 158 patients

PURPOSE: To assess the problems seen in 158 patients with coralline hydroxyapatite (HA) orbital implants (Bio-Eye). METHODS: A consecutive case series of 170 patients receiving coralline HA implanted by two surgeons over a 5-year period were reviewed. The authors analyzed age, type of surgery, implant size, peg system, follow-up duration, time of pegging, problems encountered, and treatment. RESULTS: Twelve patients were lost to follow-up after 5 months, leaving 158 patients who were followed from 6 to 130 months (average, 39 months). Problems in unpegged implants occurred in 36 (22.8%) patients. Discharge occurred in 18 (11.4%) patients, implant exposure in 12 (7.6%), socket discomfort in 1 (0.6%), conjunctival thinning in 3 (1.9%), chronic conjunctival swelling in 2 (1.3%), and implant infection in 3 (1.9%). Problems after pegging occurred in 68 (50.7%) of 134 patients: discharge in 27 (20.1%), pyogenic granuloma in 24 (17.9%), conjunctiva overgrowing the peg in 4 (3.0%), implant exposure around the sleeve in 5 (3.7%), clicking in 6 (4.5%), peg on an angle in 2 (1.5%), loose sleeve in 1 (0.7%), peg falling out in 18 (13.4%), popping peg in 1 (0.7%), poor transfer of movement in 3 (2.2%), pain with movement in 1 (0.7%), and implant infection in 2 (1.5%). CONCLUSIONS: The Bio-Eye orbital implant represents a porous orbital implant that is biocompatible with orbital tissues and allows fibrovascular ingrowth and improved motility when coupled to the overlying artificial eye. It is more expensive than other commercially available porous orbital implants, such as synthetic FCI3 HA, porous polyethylene (Medpor), and aluminum oxide (Bioceramic) implant. Problems encountered with its use are similar to those problems seen in patients with the synthetic FCI3 hydroxyapatite and aluminum oxide orbital implants.     

Effects of hyperbaric oxygen therapy on hydroxyapatite orbital implant vascularization in rabbits

PURPOSE: To deterrmine if hyperbaric oxygen therapy affects the rate of hydroxyapatite orbital implant vascularization in normal rabbit orbits. METHODS: We performed a randomized comparative experimental pilot study involving 6 rabbits. All rabbits were enucleated and implanted with hydroxyapatite orbital spheres. The animals were randomized for enucleation of the right or left eye and for treatment or nontreatment (control) with hyperbaric oxygen. The implants were removed after 3 weeks of treatment and histologically examined for fibrovascular ingrowth, inflammation, and multinucleated giant cells. Each parameter was graded on a numeric scale and analyzed. RESULTS: Hyperbaric oxygen therapy did not increase implant vascularization compared with nontreatment implants. Although treated implants had less central fibrovascular maturity compared with control implants, the difference was not statistically significant (p < 0.055). There was no significant difference in inflammation or the number of multinucleated giant cells between treated and control implants. CONCLUSIONS: In this pilot study, hyperbaric oxygen therapy did not increase hydroxyapatite vascular ingrowth and possibly delayed fibrovascular maturation in normal sockets. Further studies with more subject numbers are needed to confirm these conclusions. The effect of hyperbaric oxygen therapy in vascularly compromised sockets also needs to be determined.     

Fibrovascular ingrowth into hydroxyapatite and porous polyethylene orbital implants wrapped with acellular dermis

PURPOSE: Acellular dermis is a frequently used wrapping material for hydroxyapatite (HA) and porous polyethylene (PP) orbital implants. In an animal model, we determined by histology the extent of fibrovascular ingrowth within orbital implants wrapped in acellular dermis at 6 and 12 weeks after surgery. METHODS: Four Yucatan minipigs were used for the study. Two minipigs had HA implants and two had PP implants. Implants were harvested at 6 or 12 weeks after surgery and were examined histologically for fibrovascular ingrowth. RESULTS: There was complete fibrovascularization of HA implants harvested at both 6 and 12 weeks after surgery. The PP implant harvested at 6 weeks had incomplete fibrovascularization, whereas the PP implant harvested at 12 weeks had complete fibrovascular ingrowth. There was no histologic evidence of inflammation seen in any of the orbital implants. On gross and histologic examination, the wraps were found to persist on the surface of all orbital implants, with little histologic evidence of inflammation localized to the acellular dermis. CONCLUSIONS: Acellular dermis wraps support fibrovascularization of both HA and PP orbital implants. Additionally, acellular dermis does not incite significant inflammation in association with HA and PP orbital implants and can persist in situ for at least 12 weeks after surgery.